Abstract In this study, we identify a seasonal bias in the ocean color satellite-derived remote sensing reflectances (${{\rm R}_{{\rm rs}}}(\lambda);\;{{\rm sr}^{- 1}}$) at the ocean color validation site, Marine Optical BuoY. The seasonal bias in ${{\rm R}_{{\rm rs}}}(\lambda)$ is present to varying degrees in all ocean color satellites examined, including the Visible Infrared Imaging Radiometer Suite, Sea-Viewing Wide Field-of-View Sensor, and Moderate Resolution Imaging Spectrometer.